There are 1 questions in this calculation: for each question, the 1 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ first\ derivative\ of\ function\ \frac{({x}^{3} - cos(x) - 1)}{5}\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = \frac{1}{5}x^{3} - \frac{1}{5}cos(x) - \frac{1}{5}\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( \frac{1}{5}x^{3} - \frac{1}{5}cos(x) - \frac{1}{5}\right)}{dx}\\=&\frac{1}{5}*3x^{2} - \frac{1}{5}*-sin(x) + 0\\=&\frac{3x^{2}}{5} + \frac{sin(x)}{5}\\ \end{split}\end{equation} \]

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